Airdrop systems have been use for many decades to perform delivery from airplanes. In its simplest form a package is dropped from a moving airplane such that forward momentum carries the package towards the intended ground location. This simple solution has long been used to provide humanitarian aid in areas plagued by famine, natural disasters or war.
Alternatively some slightly more advanced systems make use of parachutes, airfoils, or gliders or the like. Those devices reduce landing impact forces, and allow for “soft landings” in order to protect the dropped cargo. Still more recent configurations include electronic flight controllers that may be used to calculate or predict the flight path of a parachute or glider in order to increase precision of the flight path or to provide feedback and control of flight surfaces to steer the package towards the designated landing location.
Air drops have need to deliver goods as close as possible to the end user in order to reduce secondary transit modes such as truck or hand delivery, and may take place in congested locations where buildings, persons or vehicles may be present in the vicinity of air drop operations. Therefore it is critical that air dropped packages land within a designed landing sites and do not accidentally hit uninvolved structures or persons. Landing zones must therefore be large enough to account for the inherent inaccuracy of parachute or glider approaches, and clear of tall obstructions on approach path.
Conventional Air drop systems today attempt to address the need for delivery accuracy through the use of parachute or parafoil structures with an underslung load commonly consisting of a pallet, box, or bag.
The main drawback with parachute structures and other comparable structures used in the art today is that such devices are not able to provide sufficient guidance or control in all weather conditions such as high wind. Accurate landings cannot be guaranteed in such adverse conditions. In addition to landing inaccuracy, parachute and comparable structures are fragile and can be damaged in adverse conditions. For example, a controllable parachute with a low forward airspeed is also subject to collapse or loss of lift from a tailwind.
Another drawback to existing systems in the art is that parachute or comparable systems require large surface area chutes relative to the package size. The result is that the parachute or similar device may become entangled in trees, power lines, light poles or other ground obstructions near the landing location.
Yet another drawback is that parachutes are designed for a specific wing loading range and thus may only operate in a narrow performance window for minimum and maximum payload capacity. This limitation requires the use of multiple parachute sizes or ballast weights in order to cover a broad range of package weights.
In addition, parachute performance characteristics also require the use of secondary systems or multi parachute deployments in order to operate at the cruising speed and altitudes common to commercial cargo aircraft. The reason being that parachutes are designed for a target wing loading and cannot adapt to a wide range of load capacities while maintaining acceptable performance. These problems with parachute and parafoil performance increase the weight of the deployed system overall, and moreover decrease accuracy. The result is also increased cost and complexity. Moreover, the inherent inaccuracy and inability for controlled parachute systems to reliably land in all weather conditions requires the use of large landing zones generally relegated to fields of several acres or larger and to take place away from structures, or ground personnel that may be inadvertently struck by landing parachutes or packages.
Alternatively, powered or unpowered gliders may also be used to deliver cargo airdropped from airplanes. Similar to parafoils, gliders employ aerodynamic lift in order to reduce vertical descent rate and control surfaces to increase precision of landing. However, gliders require a large wingspan in order to maintain a suitable glide ratio generally greater than 10:1, and also require strong materials in order to maintain structural rigidity at launch speeds typical of cargo aircraft.
Conventional airdrop systems moreover have the drawback that they are not suitable for performing routine commercial delivery in developed or urban regions in which a heightened need for precision landing accuracy and flight during adverse weather conditions may exist. In addition, conventional airdrop systems are expensive, inaccurate and complex to integrate into traditional air cargo operations and thus are primarily used to support military operations, or relegated for special use cases away from ground activity. The present invention solves these and other problems.